Field of the Invention
The present invention relates to protection barriers and laser irradiation systems.
Description of the Related Art
In a distribution conveyor system, conventionally, an object to be transported (a baggage or a container) can be identified by attaching, by means of an auto labeler, an adhesive label, to which necessary information, such as shipping address, and barcode, is printed, to the object transported by a conveyor.
Recently, a reversible thermosensitive recording medium, which colors and erases with heat, has been applied as a label for a transporting container for a distribution conveyor system, in view of energy saving, and protection of the environment. Systems for printing an object to be transported (irradiation target) in a non-contact manner using a laser device have been proposed (see, for example, Japanese Unexamined Patent Application Publication No. 2009-183959).
Laser light used for label printing in such a system is extremely strong, and may burn or damage eye sight, if the laser light is directly applied to skin or eyes of humans. Accordingly, a protection barrier is installed in a working environment where people may come close to a laser device during printing, in order to adjust the laser exposure to human bodies to a safe level.
Conventional protection barriers cover objects to be transported on a conveyor, and the entire conveyor, and are in a large scale. There are however problems that an installation space is not sufficiently secured when a laser device replaces the existing auto labeler of the conveyor system, and the number of installation steps is large. As a size of an object to be transported, and a width of a conveyor for use are different depending on a user, moreover, a conventional protection barrier has a problem that it is necessary to design each protection barrier for each particular purpose, and the protection barrier lacks in versatility. Accordingly, a protection barrier that is small in the size, and highly versatile has been considered for use.
However, laser light may be leaked from the small protection barrier, as it is difficult to cover objects to be transported and an entire conveyor with the small protection barrier.